35... d3f2 [%c_effect f2;square;f2;type;Inaccuracy;persistent;true] 36. d1e1 [%c_effect e1;square;e1;type;Mistake;persistent;true] An unfortunate choice of square. Both 36.Rf1 and 36.Rg1 are stronger. 36... f2e4  37. b1c2  37... a7c7 